Refractory roof



June 8, 1965 N. NAPORA 3,187,695

REFRACTORY ROOF Filed Nov. 29, 1963 2 Sheets-Sheet l I N VEN TOR. MIA 0445 4 4/ 034 June 8, 1965 N. NAPORA 3,187,695

REFRACTORY ROOF Filed Nov. 29, 1963 2 Sheets-Sheet 2 A Tram/v5) United States Patent 3,187,695 REFRACTORY ROGF Nicholas Napora, Pittsburgh, Pa, assignor to Harbison- Walker Refractories Company, Pittsburgh, Pa, a (391? poration of Pennsylvania Filed Nov. 29, 1963, Ser. No. 326,940 4 Claims. (Cl. 110-99) The present invention relates to furnace roof construction, and is particularly directed to the construction and suspension of basic brick units for such roofs.

In the production, refinement and other treatments of various metals, the construction and maintenance of the roof of the furnace employed constitutes a substantial element in the cost of such operations. Many proposals have been made from reducing such cost and increasing the efiiciency of operation of roofs of this character. For example, sockets have been formed in, or lugs on, the brick for receiving the suspending means; and the adjoining faces of brick have been corrugated to receive and hold a suspending metal plate. Brick for use in furnace arched roofs have been given various interlocking shapes.

A conventional procedure for installing many prior basicroofs of the sprung arch type, whether suspended or unsuspended, was to provide wooden forms on which bricks were placed. Many such roofs used I-bearns running from end to end longitudinally of the furnace axis and at different horizontal levels, depending upon the arch, to form the roof cont-our. These beams were in turn mounted, sometimes yieldingly, on a rigid furnace superstructure. Tie plates were also provided between courses of brick and perpendicularto the I-beams, at spaced intervals. Frequently, the brick were suspended from the tie plates individually on wire hangers. Also, the individual brick had been notched, in some manner, and thereby weakened to provide for hanging or suspension.

Metal encased refractory brick were often suspended by hangers from overhead supports. Usually the hangers were relatively expensive separate castings that had to be hooked into the blocks as the roof was being formed.- This required the handling of a large number of separate articles and the separate connection of each hanger to an individual block by the workmen hanging the roof, all of which was time consuming.

Other methods have also been proposed; for example, see Patent No. 2,781,006. Here it was proposed to fabricate a furnace roof by disposing adjacent courses of brick, so that certain courses were secured to a beam with wire by the use of perforated hanger members which were integral with the metal casing on the brick.

Accordingly, it is an object of this invention to provide a new sprung arch furance roof construction which may be installed readily at a minimum cost and with a minimum number of parts. 7

Another object of the invention is to provide hanger tabs integral with metal plates on one end of a brick, and to unite the same to a supporting structure.

A still further object of the invention is to construct a basic furnace roof using ribs consisting of at least one row of supported brick attached to a supporting structure running above the same by hanger tabs integral with the metal surface plate on the brick, and having an intervening row or rows of brick relatively shorter than those first mentioned and freefrom separate suspension.

Other objects of the invention will appear hereinafter.

In order to understand more fully the nature and objects of the invention, reference should be had to the following detailed description and drawings of which:

FIG. 1 is a fragmentary perspective view of a roof of an open hearth furnace constructed in accordance with disposed below the suspending beams.

3,187,695 Fatented June 8, 1965 the invention, showing the manner in which the basic brick are secured in place;

FIG. 2 is a perspective View of a metal encased, wedge shaped basic brick of regular construction, having metal integral hanger tabs and employed in the improved roof construction; and

FIG. 3 is an enlarged fragmentary perspective view, showing a manner in which the brick are assembled.

In accordance with the present invention, a series of spaced brick suspending means extend over a furnace and terminate at skewbacks disposed on sides of the furnace. Each beam contains a pair of flanges extendingupw-ardly in a substantially identical direction. A series of adjacent, alternately arranged rib and valley courses of metal encased basic brick (i.e two-rib, fourvalley'sequence) are i The brick in the rib courses are in contiguous relation with the undersurface of the beam at one end surface of the brick. The brick in each rib and valley course across the span of the arch are in contiguous relation with the next adjacent brick in the same course at the face surfaces thereof. The

' face of the brick that abuts the brick in the next adjacent valley course. A portion of each hanger tab is bent over the upper extremity of a flange so as to be secured thereto;

Thus, all of the brick in the rib course are fixed in place i by means of the hanger tabs. The brick in the rib courses project above the upper end surfaces of the brick in the valley courses, and the inner surface of the roof is smooth. Brick in the valley courses may be supported or sprung in the usual manner employing skewbacks. However, since all of the brick in adjacent courses are in contiguous relation with each other, in operation, the metal-clad brick fuse together and bridge across the adjacent brick courses to assist in supporting the valley course brick without external support means. Rib and valley course patterns are advantageous since, in service, as the roof gradually wears thinner, the brick in the ribs remains strong even after the intervening valleyhad become too thin for stability. The stability of the ribs is especially advantageous if the roof wears away much more rapidly in some places than others. Their additional strength is very helpful when roofs must be patched.

In FIG. 1, an arched roof for an open hearth furnace is generally indicated at 10. However, it should be understood that the improved construction may be used for the roof of any other metallurgical furnace. It is composed of a plurality of spaced rib courses 12 containing brick 14 with adjacent arched valley courses 16 containing brick 18 disposed therebetween. The rib courses 12 differ from the valley courses 16, in that the brick forming the ribs are longer than those forming the courses 16. Each rib course 12 of brick includes a plurality of similar wedge shaped brick 14, which are separately attached to an arched support channel 20. A plurality of such channels 20 are disposed at longitudinally spaced intervals across the top of the furnace roof 10, and have been secured at front and back walls in a similar manner.

. The courses 12 and 16 of brick 14 and 18, respectively,

rest upon skewbrick 22., which rest upon a front wall 24 and, similarly, on the back wall (not shown) of the furnace. In addition, the lower front ends of the arched channels 20 are fixedly attached to the upper flange of a beam member 26 above the skews 22.

As shown in FIG. 2, each regular brick 14 in the rib courses are composed of a solid, unnotched block, internally plated or reinforced, if desired, of refractory material 30; such as, magnesite, chrome ore, mixtures 3 thereof, and the like, contained within a metal casing 32 on the face surfaces 34 and on the side surfaces 36 of the brick. However, it should be appreciated that a lesser number of face surfaces and side surfaces need be metal encased as long as at least-one side surface contains a metal plate. The upper and lower ends 38 and 41, respectively, of the brick are not encased. In addition, the casing 32 is provided with a hanger tab 40 projecting upward from the side surface 36 of the brick, which is preferably integral with the casing.- However, the hanger tab 40 may be a separate metal piece secured to the casing as by welding, where the tab space cannot be fabricated readily as an integral part of the casing.

Initially, the hanger tabs 40 project unidirectionally upwardly fom the side surface 36 of the brick. A portion 44 of the hanger tab is then bent to an acute angle to the remainder, approximately at the dotted line B in the drawing, to provide an inverted I-shape,-so that the tabs 40 can be engaged with the flange 42 as shown in FIG. 3. The hanger tab may contain means at B to facilitate bending by hand, such as, continuous perforations or a corrugation. Absent the bending means, any

suitable mechanical means may be employed to bend the tab.

The brick 14 have a wedge shape with the upper en 38 between side surfaces 36 being thicker than the lower end 41 so that when placed together. the brick form the arched rib courses 12, as shown in FIG. 1. The brick 18 in the valley courses 16, shown more clearly in FIG. 3, are of similar shape as the brick 14 in the rib courses 12,

except that these brick are smaller in size from end to end and do not contain hanger tabs.

The manner in which the brick 14 in rib courses 12 are attached to the arch beams 20 is also more particularly shown in FIG. 3. Each beam 20 is in the shape of a channel, with a pair of upwardly extending peripheral flanges. Each brick in the rib courses 12 is secured by the tabs 40 to one of the flanges 42. The bent portion 44 of the hanger tab 40'is disposed on a flange, so that it hooks around the upper extremity of the flange. The undersurface of the beam, preferably, is of sufficient area to cover the upper ends 38 of each pair of brick in the rib courses. The brick 14 in each rib course 12 abut, or are in contiguous relation with, next adjacent brick in the same course, so that the brick are held in place to prevent them fromslipping out of hooked engagement with the flange 42. The brick 18 in the valley course are held in place in the usual manner by the use of the skewback, or by fusion to brick 14.

Also, the brick in each individual course are in contact with one or more of the brick in adjacent courses at the side surfaces 36, so that, in operation, the metal-clad basic brick fuse together and bridge across the adjacent brick courses. to assist in supporting the valley brick Without external support means. The upper ends 38 of each brick 14 in the rib courses 12 are in flat surface abutment with the undersurface of the channel 20, and, as shown in FIG. 1, the opposite ends of the channel are secured to beams 26 or the like, so that each channel is held in place. Thus, the brick 14 in the rib courses will not rise, due to an expansion of the lower end portions of the brick, as was the case in many prior basic brick roofs Also, the brick 14 in the rib. courses 12, owing to their contiguous relation with the brick 18 in the valley courses 16, will tend to support these brick and prevent them from heaving or swelling upwardly. It is preferred, '-to maintain the structural integrity of the furnace roof, that the brick be laid in two-rib, four-valley sequence.

The channels 20 perform the double function of holding up and holding down each individual brick in the rib course. Channels 20, in turn, are held in a fixed position by beams 21, which are secured thereto by straps 23 as is shown in FIGURES 1 and 3. The beams 21 are secured to the furnace superstructure 28 by means of rods 25. The channels are each rigid members composed of a durable material, such as, steel.

A description of the improved open hearth roof construction is by way of example; and the scope of the in vention is not limited to the exact details illustrated, or to the specific sizes of brick and roof shown, or to the particular refractory composition of basic brick described, since these details, sizes and composition may be varied to suit the conditions or specification of any particular furnace involved.

, It is, therefore, intended that the above description and drawings be construed as illustrative, and not in limitation of the invention.

We claim:

1. In a basic furnace roof construction, a series of spaced, brick suspending and hold-down channels extending over the furnace and having opposite ends terminating at skewbacks disposed on sides of the furnace, each channel having a pair of flanges extending upwardly in a substantially identical direction, a series of adjacent alternately arranged rib and valley coursesof metal encased basic brick, each brick having generally opposed end, face and side surfaces, the brick in the rib courses being in contiguous relation with the undersurface of the channel at one end surface thereof, said relation holding the brick in lateral alignment with their corresponding channels, the undersurface of the channels being of sufficient area to cover completely the end surfaces of a pair of brick in adjacent rib courses, the brick in each individual course across the span of the arch being in contiguous relation at the. face surfaces thereof, the brick in adjacent courses being in contiguous relation at the side surfaces thereof, each brickin the rib course only having a hanger tab integral with the casing projecting .unidirectionally upwardly from the side surface of the brick that is contiguous with the brick in the valley course, a portion of each hanger tab being bent over the upper extremity of a flange and secured thereto, so that each brick in the rib course is suspended from and supported by said hold down channels, and brick in adjacent rib courses support one another.

2. The construction defined in claim 1, in which the ribs and valleys contain 2 courses and 4 courses, respectively, in sequence.

3. The construction defined in claim 1, in which a series of spaced support beams are disposed above and in close abutment with the brick suspending beam and are normal thereto. 7

4. The construction defined in claim 1 in which the hanger tab integral with the casing is of substantially the same thickness as the casing and is a relatively narrow portion of the distance between the ends of the casing or the side surface thereof.

References Cited by the Examiner UNITED STATES PATENTS 2,158,759 5/39 Morlock 1l099 2,512,439 6/50 Richards 122-498 2,781,006 2/57 Heuer 1l099 2,932,265 4/ 60 Heuer 1l099 3,092,051 6/ 63 Shapona et al 1l099 FOREIGN PATENTS 1,187,813 3/59 France.

623,230 12/35 Germany.

938,265 2/ 56 Germany.

PERCY L. PATRICK, Primary Examiner.

ROBERT A. DUA, JAMES W. WESTHAVER,

' Examiners. 

1. IN A BASIC FURNACE ROOF CONSTRUCTION, A SERIES OF SPACED, BRICK SUSPENDING AND HOLD-DOWN CHANNELS EXTENDING OVER THE FURNACE AND HAVING OPPOSITE ENDS TERMINATING AT SKEWBACKS DISPOSED ON SIDES OF THE FURNACE, EACH CHANNEL HAVING A PAIR OF FLANGES EXTENDING UPWARDLY IN A SUBSTANTIALLY IDENTICAL DIRECTION, A SERIES OF ADJACENT ALTERNATELY ARRANGED RIB AND VALLEY COURSES OF METAL ENCASED BASIC BRICK, EACH BRICK HAVING GENERALLY OPPOSED END, FACE AND SIDE SURFACE, THE BRICK IN THE RIB COURSES BEING IN CONTIGUOUS RELATION WITH THE UNDERSURFACE OF THE CHANNEL AT ONE END SURFACE THEREOF, SAID RELATION HOLDING THE BRICK IN LATERAL ALIGNMENT WITH THEIR CORRESPONDING CHANNELS, THE UNDERSURFACE OF THE CHANNELS BEING OF SUFFICIENT AREA TO COVER COMPLETELY THE END SURFACES OF A PAIR OF BRICK IN ADJACENT RIB COURSES, THE BRICK IN EACH INDIVIDUAL COURSE ACROSS THE SPAN OF THE ARCH BEING IN CONTIGUOUS RELATION AT THE FACE SURFACES THEREOF THE BRICK IN ADJACENT COURSES BEING IN CONTIGUOUS RELATION AT THE SIDE SURFACES THEREOF, EACH BRICK IN THE RIB COURSE ONLY HAVING A HANGER TAB INTEGRAL WITH THE CASING PROJECTING UNIDIRECTIONALLY UPWARDLY FROM THE SIDE SURFACE OF THE BRICK THAT IS CONTIGUOUS WITH THE BRICK IN THE VALLEY COURSE, A PORTION OF EACH HANGER TAB BEING BENT OVER THE UPPER EXTREMITY OF A FLANGE AND SECURED THERETO, SO THAT EACH BRICK IN THE RIB COURSE IS SUSPENDED FROM AND SUPPORTED BY SAID HOLD DOWN CHANNELS, AND BRICK IN ADJACENT RIB COURSES SUPPORT ONE ANOTHER. 